Fluids/Electrolytes/Acid/Base Flashcards
Definition of Electrolyte
POS or NEG Charged molecules that give off ions when dissolved in H2O
Cation = POS
Anion = NEG
Extracellular fluid
#3, how much contributes to TBW?
how is ECF divided?
- space w/i intravascular blood vessels = 4%
- Interstitial fluid w/i tissue = 15%
- Transcellular = 1%
* bile, CSF, synovial, glandular
Interstitial is 75% of ECF
Intravascular is 25% of ECF
Total = 1/3 total body water (approx 20% of bw)
Intracellular Fluid
#3, how much contributes to TBW?
- Space w/i the cells and fluid
- Gives shape/form/functionality
- Largest Volume of fluid in the body is INTRACELLULAR
Total = 2/3 of total body water (approx. 40% bw)
Define:
Solutes
Ions
Electrolytes
- water w/ dissolved substances w/i all body compartments
- POS or NEG charged molecules
- Substances given off when dissolved in water from ions → Na+/K+/Cl-/Ca++/Mg++/Phos
Na+/K+ ATPase Pump
Intracellular Pump that ensures Na+ gets removed from cell and K+ stays intracellular
* majority of Na+ extracellular → 140meq/L ECF (pulls Cl- with)
* Majority of K+ intracellular (140meq/L ICF)
Ex: Beta Blockers → propanolol blocks Na+/K+ ATP pump
Intracellular Cation and Anions
Cations = K+ Mg++
Anions = Phos (needed for ATP and to bind to glucose)
* Blood proteins (mainly NEG charged)
Extracellular Cations and Anions
Cations = Ca++, Na+ (Na+/K+ pump)
Anions = Cl- → net from Na+/K+ pump
* HCO3- →ECF reserves are alkaline to buffer acids inside the cell
* Cl- → follows Na+
Anion Gap
Difference between measured Cations and anions in the blood
–numerous unmeasured anions = ↑
anion gap to maintain zero net electric plasma charge (Cations and Anions must always equal)
Normal K9= 10-24 mmol/L Fel= 13-27 mmol/L
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Examples of unmeasured Anions
Lactate
Ketones
Ethylene glycol
Uremia
Aspirins
Alcohols
cyanide
OsmolARITY
concentration of a solution expressed as mOsm/L
LAR=LITER
OsmolALITY
concentration of a solution expressed as mOsm/kg
Normal = K9 = 290-310 mOsm/kg Fel= 290-330 mOsm/kg
Tonicity
3 types
Ability of extracellular solutions to move water in or out of cell via osmosis
Isotonic = do not cause changes in h20 movement across cell membrane
Hypotonic = tonicity LESS than plasma causes H2O to move INTO cells
Hypertonic = tonicity HIGHER than plasma, causes fluid to move OUT of cells into fluid
“effective osmolality”
Osmotic Pressure
Definition
Effects of HyperNa+ and HypONa+ on water
Pressure needed applied to H20 to prevent osmosis (movement of water)
HyperNa+ → cells volume loss due to osmotic gradient pushing water into hyperosmolar extracellular space
HypoNa+ → cells SWELL as H2O gets pushed into cells
Ex: Na+ and Glucose
WATER FOLLOWS Na+
Ca++ ATP pump
What is it exchanged for?
Which system utilizes this?
Ca++ moves outside cell when Na+ shifts intracellularly
“couter-transport”
– enters the plasma by absorption from the gastrointestinal tract regulated by vitamin D and by resorption from the bones.
– leaves the plasma by secretion into GIT, urinary excretion, and deposition into bones
–important for muscle activity/contrations
–nerve impulse transmissions
–blood clotting
Ex: Digoxin → inhibits Na+/K+ ATP exchange, Na+ stays in ECS → Ca++ stays ICS for contractility improvement
H+ ATPase pump
– H+-K+-ATPases are ion pumps that use the energy of ATP hydrolysis to transport protons (H+) in exchange for (K+).
– Dumps acid ASAP in metabolic acidosis
Proximal Convuluted tubule in Kidney
HCO3 is later reabsorbed as buffer
Free water deficit definition
–determines the volume (L) of water required to correct dehydration or, to reach the desired level of sodium in the blood serum
Does Not Follow Lytes
H2O w/o solutes
–Kidney depends on Free H2O to concentrate/dilute urine influenced by ADH
–Deficits occur w/ solute-free water loss from body
2nd to CKD/D+/V+/Panc/Peritonitist/FBO/DI/Adipsia/Lack of water access
Law of Electroneutrality
any single ionic solution, sum of negative charges attracts an equal sum of positive chargers concentration of cations = concentration of anions
Na+ review
Normal vs Disturbances
Normal actions: TBW inverse relation with Na+
–fluid regulation
osmosis → H2O FOLLOWS Na+
Distrubances: cells shrink or swells w/i brain → mental abnormalities
–free water deficit
–toxicity (play dough)
–sz/ataxia/behavioral changes/lethargy
Main Na+ ECF cation
K+ Review
Normal vs Disturbances
Normal actions: resting membrane potential → needed for action potential and repolarization of myocaridal cells
–absorbed in SI/excreted by kidneys and colon
Disturbances: membrane potential problems → arrhythmias
–affected by acid-base disturbances → low pH = high K+; high pH = low K+
–affected by lack of insulin
–Reperfusion syndrome → increase in insulin stimulates intracellular uptake of K+/phos-
–bradycardia/tall T-waves/ Small P-waves
Intracellular cation (99%)
Ca++ Review
Normal vs Disturbances
where is it stored?
What regulates it?
Normal actions: stored in bones; absorbed thru diet
– HypOCa++ = ↑ permeability to Na+ → action potential = ↑↑ excitability
– HypERCa++= ↓ permeability to Na+ = ↓ action potential = ↓↓ excitability
–PTH controls ECF Ca++ (and Phos) Calicitonin via C-cells
Mg++ Review
Normal vs Disturbances
where is it stored/absorded?
what transports is it apart of?
Normal actions: stored in bones/absorbed in SI
–affects active transport or Na+/K+ ATP pump
–blocks Ca++ channels intracellularly
Disturbances: Nerve/muscle problems → twitching/ faciculations
–arrhythmias
–associated with other lyte derangements → refractory hyPOCa++/hyPO K+ (active transport)
Cl- Review
Normal vs Disturbances
Where is it absorbed? What is it reguated by?
Normal actions: Needed for acid/base balance
–absorbed from diet
–regulated by kidney
Disturbances: associated with body water disturbances
–will cause opposite changes to HCO3 → hyPO will raise, hyPER will lower
– ↓ with GI losses
Major Extracellular Anion
Phos Review
Normal vs Disturbances
What is responsible for regulating it?
Normal actions: absorbed/excreted along with Ca++
–Mineral for bone strength
–ATP phos bond carries energy for ALL CELL functions
–buffers bone/serum/urine
Disturbances: ↑ PTH = ↑ Ca++ = ↑ Phos excreted = hyPOphos
– ↓ GFR = ↓ Phos excreted =hypERphos
–Insulin causes Phos to shift intracellularly
–Refeeding syndrome
Major intracellular Anion
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ECF Osmoles
Na+
Glucose
Urea
K+
Cl-